I have no idea what's going on in your particular situation but I want to throw a few thoughts out there.
Alcohol or lack there of is not responsible for all issues in a person's life. Don't give it any more power or slack than it deserves. I have seen many people, both the alcoholics themselves and their loved ones use drinking or having stopped drinking as an excuse for all kind of behavior.
Relationships start and end everyday alcohol or no alcohol. Look at the quality of the relationship and the words and behaviors. Judge it on it's own merit and make decision from that standpoint.
You are responsible for yourself and your child. Even if he is an alcoholic or a recovering alcoholic he is still an adult.